Stable Shellac Enteric Coating Formulation for Nutraceutical and Pharmaceutical Dosage Forms

Abstract

The present invention relates to formulations for use as enteric coatings. More particularly, the present invention relates to a formulation comprising a blend of food grade ingredients that can be readily dispersed in water. This dispersion exhibits low viscosity and can easily be coated onto solid dosage forms through spraying and the like to provide an enteric coating on the solid dosage form.

1 . A formulation in powder form useful for producing a sprayable dispersion for enteric coating, comprising:
 a food grade shellac, and   a non-ammonium alkali salt.   
     
     
         2 . The formulation in powder form of  claim 1  wherein the non-ammonium alkali salt comprises a nonvolatile inorganic or organic salt. 
     
     
         3 . The formulation in powder form of  claim 1  wherein the non-ammonium alkali salt is selected from the group consisting of sodium bicarbonate, sodium carbonate, calcium hydroxide, calcium bicarbonate and calcium carbonate, potassium bicarbonate, and potassium carbonate. 
     
     
         4 . The formulation in powder form of  claim 1  wherein the non-ammonium alkali salt comprises sodium bicarbonate. 
     
     
         5 . The formulation in powder form of  claim 1  wherein the formulation in powder form further comprises a water-miscible polymer selected from the group consisting of alginate salt, alginic acid, proteins, methylcellulose (MC), hydroxypropylcellulose (HPC), hydroxypropylmethylcellulose (HPMC), carboxymethyl cellulose (CMC), pectin, carrageenan, guar gum, locust bean gum, xanthan gum, gellan gum and arabic gum. 
     
     
         6 . The formulation in powder form of  claim 5  wherein, water-miscible polymer comprises an anionic polymer selected from the group consisting of sodium carboxymethyl cellulose (CMC), sodium alginate and pectin. 
     
     
         7 . The formulation in powder form of  claim 6  wherein the anionic polymer comprises sodium carboxymethyl cellulose (CMC) in an amount in the range of from about 1% to about 18% by weight of the formulation in powder form. 
     
     
         8 . The formulation in powder form of  claim 6  wherein the anionic polymer comprises sodium alginate in an amount in the range of from about 1% to about 50% by weight of the formulation in powder form. 
     
     
         9 . The formulation in powder form of  claim 1  wherein the food grade shellac is Orange Dewaxed Shellac in an amount in the range of from about 20% to about 75% by weight of the formulation in powder form. 
     
     
         10 . The formulation in powder form of  claim 1  wherein the non-ammonium alkali salt of use in the formulation in powder form comprises in the range of from about 1.0% to about 10% by weight of the formulation in powder form. 
     
     
         11 . The formulation in powder form of  claim 1  further comprising one or more plasticizers chosen from the group consisting of glycerine, propylene glycol, mineral oil, triacetin, polyethylene glycol, glyceryl monostearate, acetylated monoglyceride, polysorbate, oleic acid, and glyceryl tricaprylate/caprate. 
     
     
         12 . An enteric coated nutraceutical or pharmaceutical solid dosage form comprising, a nutraceutical or pharmaceutical active ingredient, and an enteric coating wherein the enteric coating comprises:
 a food grade shellac, and   a non-ammonium alkali salt.   
     
     
         13 . The enteric coated nutraceutical or pharmaceutical solid dosage form of  claim 12  wherein enteric coating further comprises a water-miscible polymer selected from the group consisting of alginate salt, alginic acid, protein, methylcellulose (MC), hydroxypropylcellulose (HPC), hydroxypropylmethylcellulose (HPMC), carboxymethyl cellulose (CMC), pectin, carrageenan, guar gum, locust bean gum, xanthan gum, gellan gum and arabic gum. 
     
     
         14 . The enteric coated nutraceutical or pharmaceutical solid dosage form of  claim 13  wherein the water-miscible polymer comprises an anionic polymer selected from the group consisting of sodium carboxymethyl cellulose (CMC), sodium alginate and pectin. 
     
     
         15 . The enteric coated nutraceutical or pharmaceutical solid dosage form of  claim 14  wherein the anionic polymer comprises sodium carboxymethyl cellulose (CMC) in an amount in the range of from about 1% to about 18% by weight of the enteric coating. 
     
     
         16 . The enteric coated nutraceutical or pharmaceutical solid dosage form of  claim 14  wherein the anionic polymer comprises sodium alginate in an amount in the range of from about 1% to about 50% by weight of the enteric coating. 
     
     
         17 . The enteric coated nutraceutical or pharmaceutical solid dosage form of  claim 12  wherein the food grade shellac is Orange Dewaxed Shellac in an amount in the range of from about 20% to about 75% by weight of the enteric coating. 
     
     
         18 . The enteric coated nutraceutical or pharmaceutical solid dosage form of  claim 12  wherein the enteric coating further comprises one or more plasticizers chosen from the group consisting of glycerine, propylene glycol, mineral oil, triacetin, polyethylene glycol, glyceryl monostearate, acetylated monoglyceride, oleic acid, glyceryl tricaprylate/caprate and polysorbate. 
     
     
         19 . The enteric coated nutraceutical or pharmaceutical solid dosage form of  claim 12  wherein the enteric coating further comprises an inorganic pigment in an amount up to about 70% by weight of the enteric coating. 
     
     
         20 . A process for producing a sprayable dispersion for enteric coating comprising the steps of:
 blending a food grade shellac, a non-ammonium alkali salt, a water miscible polymer, one or more plasticizers selected from the group consisting of glycerine, propylene glycol, mineral oil, triacetin, polyethylene glycol, glyceryl monostearate, acetylated monoglyceride, glyceryl tricaprylate/caprate and polysorbate, together to form a powder formulation,   dispersing the powder formulation in about 50 to 80° C. hot water, and stirring the dispersed the powder formulation for a sufficient period of time to produce a low viscosity sprayable dispersion.   
     
     
         21 . A process for producing a solid dosage form having an enteric coating comprising the steps of:
 obtaining a nutraceutical or pharmaceutical active ingredient in a solid dosage form,   blending a food grade shellac, a non-ammonium alkali salt, a water-miscible polymer, one or more plasticizers chosen from the group consisting of glycerine, propylene glycol, mineral oil, triacetin, polyethylene glycol, glyceryl monostearate, acetylated monoglyceride, glyceryl tricaprylate/caprate and polysorbate together to form a powder formulation,   dispersing the powder formulation in about 50 to 80° C. hot water,   mixing the dispersed the powder formulation for a sufficient period of time to produce a low viscosity sprayable dispersion, and   spraying the low viscosity sprayable dispersion onto the nutraceutical or pharmaceutical active ingredient in a solid dosage form to produce an enteric coating on the nutraceutical or pharmaceutical active ingredient in a solid dosage form.